Manually-actuated, reduced-pressure systems for treating wounds

ABSTRACT

A manually-actuated, constant reduced-pressure apparatus for use with a reduced-pressure system for treating tissue at a tissue site includes a flexible, collapsible member that is operable to move between a compressed position and an extended position. The collapsible member may be disposed between a carrier member and a slider member that move between a compressed position and an extended position. The carrier member and slider member are urged away from each other by a constant-force biasing member, e.g., a constant force coil spring. As the apparatus moves from the compressed position to the extended position, a constant reduced-pressure is generated and delivered to a reduced-pressure port. Methods of manufacturing a manually-actuated, constant reduced-pressure apparatus and methods of treating a tissue site are also provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/711,832, filed Sep. 21, 2017, which is a continuation of U.S. patentapplication Ser. No. 14/145,723, filed Dec. 31, 2013, now U.S. Pat. No.9,795,722, which is a divisional application of U.S. patent applicationSer. No. 12/500,134, filed Jul. 9, 2009, now U.S. Pat. No. 8,641,692,which claims the benefit, under 35 U.S.C. § 119(e), of the filing ofU.S. Provisional Patent Application No. 61/079,866, entitled“Manually-Actuated, Reduced-Pressure System for Treating a Wound,” filedJul. 11, 2008, which is incorporated herein by reference for allpurposes.

BACKGROUND

The present invention relates generally to medical treatment systems andparticularly to manually-actuated, reduced-pressure systems andapparatuses for treating wounds.

Clinical studies and practice have shown that providing a reducedpressure in proximity to a tissue site augments and accelerates thegrowth of new tissue at the tissue site. The applications of thisphenomenon are numerous, but application of reduced pressure has beenparticularly successful in treating wounds. This treatment (frequentlyreferred to in the medical community as “negative pressure woundtherapy,” “reduced pressure therapy,” or “vacuum therapy”) provides anumber of benefits, including faster healing and increased formulationof granulation tissue. Typically, reduced pressure is applied to tissuethrough a porous pad or other manifolding device. The porous padcontains cells or pores that are capable of distributing reducedpressure to the tissue and channeling fluids that are drawn from thetissue. The porous pad may be incorporated into a dressing having othercomponents that facilitate treatment.

Reduced-pressure treatment systems are often applied to large, highlyexudating wounds present on patients undergoing acute or chronic care,as well as other severe wounds that are not readily susceptible tohealing without application of reduced pressure. Low-severity woundsthat are smaller in volume and produce less exudate have generally beentreated with dressings and not with reduced pressure. The expense andneed for trained caregivers to administer and maintain reduced-pressuresystems have been a detriment to use. At the same time, size and powerrequirements have been a detriment to many patients who desire mobilityand comfort. Further still, the expense of systems has made it difficultto justify use of reduced pressure on low-severity wounds.

One of the challenges of treating wounds with reduced pressure isproviding an effective manner of producing a constant source of reducedpressure. Currently, battery-operated pumps are often used to provide areduced pressure to the wound site. However, these pumps are costly andrequire maintenance to ensure the batteries do not run out of powerwhile the wound therapy is occurring. The loss of battery power mayresult in a long period of time until the reduced pressure is restoredto the site due to the time involved to change the battery or make otherprovisions. Moreover, if the reduced pressure at the site is notmaintained properly, leaks can occur at the wound site limiting theeffectiveness of the reduced-pressure therapy.

SUMMARY

Problems with existing reduced-pressure sources and systems areaddressed by the systems, apparatus, and methods of the illustrativeembodiments described herein. According to an illustrative embodiment, amanually-actuated, reduced-pressure system for treating a wound on apatient includes a manifold member, a sealing member, a reduced-pressuredelivery member, a reduced-pressure interface, and a manually-actuated,constant reduced-pressure source for generating a reduced pressure. Themanifold is operable to distribute a reduced pressure. The sealingmember is operable to provide a fluid seal over the manifold member anda portion of the patient. The reduced-pressure delivery member transmitsreduced pressure from the manually-actuated, constant reduced-pressuresource to the reduced-pressure interface. The manually-actuated,constant reduced-pressure source includes a reduced-pressure port thatis fluidly coupled to a first end of the reduced-pressure deliverymember. The manually-actuated, constant reduced-pressure source includesa constant-force biasing member.

According to another illustrative embodiment, a manually-actuated,reduced-pressure apparatus for use with a reduced-pressure system fortreating tissue includes a flexible, collapsible member having a firstend, a second end, and an interior space. The flexible, collapsiblemember is operable to move between a compressed position and an extendedposition. The manually-actuated, reduced-pressure apparatus furtherincludes an evacuation port coupled to the flexible, collapsible memberand a reduced-pressure port coupled to the flexible, collapsible member.The manually-actuated, reduced-pressure apparatus has a carrier membercoupled to the first end of the flexible, collapsible member and aslider member coupled to the second end of the flexible, collapsiblemember. The slider member is operable to slidably engage the carriermember and to move between the compressed position and the extendedposition. The manually-actuated, reduced-pressure apparatus furtherincludes a constant-force biasing member associated with carrier memberand slider member and that is operable to urge the slider member andcarrier member away from each other between the compressed position andthe extended position.

According to another illustrative embodiment, a method of manufacturinga manually-actuated, reduced-pressure apparatus includes the steps offorming a carrier member, forming a slider member, and providing aflexible, collapsible member having a first end, a second end, and aninterior space. The slider member and carrier member are formed toslidably engage one another. The flexible, collapsible member ismoveable between a compressed position and an extended position. Themethod of manufacturing further includes the steps of coupling the firstend of the flexible, collapsible member to the carrier member, couplingthe second end of the flexible, collapsible member to the slider member,and associating a constant-force biasing member with the carrier memberand slider member. The constant-force biasing member is operable to urgethe carrier member and slider member away from each other between thecompressed position and extended position. The method of manufacturingfurther includes the steps of associating an evacuation port with theflexible, collapsible member for allowing fluid to exit the interiorspace of the flexible, collapsible member when being placed in thecompressed position and associating a reduced-pressure port with theflexible, collapsible member for delivering reduced pressure from theflexible, collapsible member.

According to another illustrative embodiment, a method of treating atissue site on a patient with reduced pressure includes the steps ofdeploying a manifold member proximate the tissue site, deploying asealing member over the manifold member and a portion of the patient'sepidermis to form a fluid seal, coupling a reduced-pressure interface onthe sealing member for providing reduced pressure to the manifoldmember, and providing a reduced-pressure source, wherein thereduced-pressure source is a manually-actuated, constantreduced-pressure source. The manually-actuated, constantreduced-pressure source includes a reduced-pressure port. Thereduced-pressure port is fluidly coupled to the first end of thereduced-pressure delivery member and is operable to develop asubstantially constant reduced pressure. The manually-actuated, constantreduced-pressure source includes a constant-force biasing member. Themethod of treating further includes the steps of fluidly coupling thereduced-pressure source to the reduced-pressure interface and moving thereduced-pressure source to the compressed position.

Other features and advantages of the illustrative embodiments willbecome apparent with reference to the drawings and detailed descriptionthat follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic presentation of an illustrative embodiment of amanually-actuated, reduced-pressure system for treating a wound with aportion shown in cross-section and a portion shown in a perspectiveview;

FIG. 2 is a schematic, exploded perspective view of an illustrativeembodiment of a manually-actuated, reduced-pressure apparatus for usewith a reduced-pressure system;

FIGS. 3A and 3B are schematic cross-sections of a portion of theapparatus of FIG. 2;

FIGS. 4A, 4B, and 4C present an illustrative embodiment of amanually-actuated, reduced-pressure apparatus shown in a compressedposition, an intermediate position, and an expanded position,respectively;

FIG. 5 is a schematic perspective view of another illustrativeembodiment of a manually-actuated, reduced-pressure apparatus; and

FIG. 6 is a schematic perspective view of another illustrativeembodiment of a manually-actuated, reduced-pressure apparatus.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In the following detailed description of the illustrative embodiments,reference is made to the accompanying drawings that form a part hereof.These embodiments are described in sufficient detail to enable thoseskilled in the art to practice the invention, and it is understood thatother embodiments may be utilized and that logical structural,mechanical, electrical, and chemical changes may be made withoutdeparting from the spirit or scope of the invention. To avoid detail notnecessary to enable those skilled in the art to practice the embodimentsdescribed herein, the description may omit certain information known tothose skilled in the art. The following detailed description is,therefore, not to be taken in a limiting sense, and the scope of theillustrative embodiments are defined only by the appended claims.

Referring to FIG. 1, a manually-actuated, reduced-pressure system 100for treating a tissue site 102 with a reduced pressure is shown. Thetissue site 102 may be the bodily tissue of any human, animal, or otherorganism, including bone tissue, adipose tissue, muscle tissue, dermaltissue, vascular tissue, connective tissue, cartilage, tendons,ligaments, or any other tissue.

The reduced pressure may be applied to the tissue site 102 to helppromote removal of exudates or other fluids from the tissue site or tostimulate the growth of additional tissue. Unless otherwise indicated,as used herein, “or” does not require mutual exclusivity. In the case ofa wound at the tissue site 102, the growth of granulation tissue andremoval of exudates and bacteria helps to promote healing of the wound.In the situation of a non-wounded or non-defective tissue, reducedpressure may be used to promote the growth of tissue that may beharvested and transplanted to another tissue site. As used herein,“reduced pressure” generally refers to a pressure less than the ambientpressure at a tissue site that is being subjected to treatment. In mostcases, this reduced pressure will be less than the atmospheric pressureat which the patient is located. Alternatively, the reduced pressure maybe less than a hydrostatic pressure at the tissue site 102. Unlessotherwise indicated, values of pressure stated herein are gaugepressures. Although the terms “vacuum” and “negative pressure” may beused to describe the pressure applied to the tissue site, the actualpressure applied to the tissue site may be more than the pressurenormally associated with a complete vacuum. Consistent with the useherein, an increase in reduced pressure or vacuum pressure typicallyrefers to a relative reduction in absolute pressure.

The manually-actuated, reduced-pressure system 100 includes a manifoldmember 110, a sealing member 114, a reduced-pressure interface 120, anda reduced-pressure source 140, which is a manually-actuated,reduced-pressure apparatus. A reduced-pressure delivery member 122fluidly couples the reduced-pressure source 140 to the reduced-pressureinterface 120.

The manifold member 110 is placed at the tissue site 102. The manifoldmember 110 may be a biocompatible material that is capable of beingplaced in contact with the tissue site and distributing reduced pressureto the tissue site. The term “manifold” as used herein generally refersto a substance or structure that is provided to assist in applyingreduced pressure to, delivering fluids to, or removing fluids from atissue site. The manifold member 110 typically includes a plurality offlow channels or pathways that distribute fluids provided to and removedfrom the area of tissue around the manifold. The flow channels may beinterconnected. Examples of manifolds may include, without limitation,devices that have structural elements arranged to form flow channels,cellular foam (such as open-cell foam), porous tissue collections, andliquids, gels and foams that include or cure to include flow channels.The manifold member 110 may be porous and may be made from foam, gauze,felted mat, or any other material suited to a particular biologicalapplication.

In one illustrative embodiment, the manifold member 110 is a porous foamand includes a plurality of interconnected cells or pores that act asflow channels. The porous foam may be a polyurethane, open-cell,reticulated foam, such as the GranuFoam® material manufactured byKinetic Concepts, Incorporated of San Antonio, Tex. Other embodimentsmight include “closed cells.” In some situations, the manifold may alsobe used to distribute fluids, such as medications, antibacterials,growth factors, and other solutions to the wound. Other layers may beincluded, such as absorptive materials, wicking materials, hydrophobicmaterials and hydrophilic materials.

The sealing member 114 is placed over the manifold member 110 andprovides a fluid seal adequate for the manually-actuated,reduced-pressure system 100 to hold a reduced pressure at the tissuesite 102. “Fluid seal,” or “seal,” means a seal adequate to hold reducedpressure at a desired site given the particular reduced-pressuresubsystem or source involved. The sealing member 114 may be a cover thatis used to secure the manifold member 110 at the tissue site 102. Whilethe sealing member 114 may be impermeable or semi-permeable, the sealingmember is capable of maintaining a reduced pressure at the tissue site102 after installation of the sealing member 114 over the manifoldmember 110 and a portion of the patient's epidermis. The sealing member114 may be a flexible over-drape or film formed from a silicone basedcompound, acrylic, polyurethane, hydrogel or hydrogel-forming material,or any other biocompatible material that includes the impermeability orpermeability characteristics desired for the tissue site 102.

The sealing member 114 may further include an attachment device 116 tosecure the sealing member 114 to a patient's skin. The attachment device116 may take many forms. For example, an adhesive layer 118 may bepositioned along a perimeter of the sealing member or any portion of thesealing member to provide the fluid seal. The adhesive layer 118 mayalso be pre-applied and covered with a release member that is removed atthe time of application.

The reduced-pressure interface 120, or connector, permits the passage offluid from the manifold member 110 to the reduced-pressure deliverymember 122 and vice versa. For example, exudates collected from tissuesite using the manifold member 110 may enter the reduced-pressuredelivery member 122 via the reduced-pressure interface 120. In anotherembodiment, the system 100 may not include the reduced-pressureinterface 120 and the reduced-pressure delivery member 122 may beinserted directly through the sealing member 114 and into the manifoldmember 110. The reduced-pressure delivery member 122 may be a medicalconduit or tubing or any other device for enabling transportation ortransmission of reduced pressure.

Reduced pressure is generated and supplied to the reduced-pressuredelivery member 122 by the reduced-pressure source 140, which is amanually-actuated, reduced-pressure apparatus. The reduced-pressuresource 140 may include a flexible, collapsible member 146 that isassociated with a carrier member 156 and a slider member 168. As usedherein, “associated” means to bring together or into relationship in anyof various ways, such as permanently coupling one to another, releasablycoupling one to another, aligning members to allow one member to push orpull another member, etc.

While not explicitly shown in FIG. 1, the reduced-pressure source 140includes a constant-force biasing member that urges slider member 168away from carrier member 156. The reduced-pressure source 140 has anevacuation port 153 that allows the air or other fluid in the flexible,collapsible member 146 to exit, but not enter the evacuation port 153.Reduced pressure is delivered by the reduced-pressure source 140 througha reduced-pressure port 154, which is coupled to the reduced-pressuredelivery member 122 and may be operable to allow flow in only onedirection—from the reduced-pressure delivery member 122 into theflexible, collapsible member 146. By using the constant-force biasingmember, the reduced-pressure source 140 is operable to develop aconstant reduced pressure. As used herein, “constant” means that aparticular reduced pressure may be maintained at the reduced-pressureport 154 at a given level plus or minus five percent. The strength ofthe constant-force biasing member is a variable for establishing thereduced pressure level produced by the reduced-pressure source 140.

A number of different devices may be added to a medial portion 124 ofthe reduced-pressure delivery member 122. For example, a fluidcollection member 126 may be added to hold exudates and other fluidsremoved (the fluids may also be held within the flexible, collapsiblemember 146). Other examples of devices that may be included on themedial portion 124 of the reduced-pressure delivery member 122 include apressure feedback device, volume detection system, blood detectionsystem, infection detection system, flow monitoring system, temperaturemonitoring system, etc. Some of these devices, e.g., the fluidcollection member, may be formed integrally with the reduced-pressuresource 140. The reduced-pressure port 154 may include a filter memberthat includes one or more filters and may include a hydrophobic filterthat prevents liquid from entering an interior space within thecollapsible member 146. An odor filter may also be included.

In operation, the manifold member 110 is deployed proximate the tissuesite 102, and the sealing member 114 is deployed to create a fluid sealover the manifold member 110 and a portion of the patient's epidermis.If not already coupled, the reduced-pressure interface 120 is coupled tothe sealing member 114. The reduced-pressure delivery member 122 iscoupled between the reduced-pressure interface 120 and thereduced-pressure source 140. The slider member 168 is manually actuatedor moved toward the carrier member 156 thereby collapsing the flexible,collapsible member 146 and placing the reduced-pressure source 140 in acompressed position. During this movement, air or other fluid in theinterior space of the flexible, collapsible member 146 is forced outthrough the outlet evacuation port 153. Then, once released, as thebiasing device urges the slider member 168 away from the carrier member156, the biasing causes the flexible, collapsible member 146 to want toexpand which generates a reduced pressure that is communicated throughthe reduced-pressure port 154 to the reduced-pressure delivery member122 and on through the reduced-pressure interface 120 to the manifoldmember 110 and to the tissue site 102. As the delivery of reducedpressure causes gases or possibly other fluids to enter thereduced-pressure port 154, the flexible, collapsible member 146 expandsand eventually fills to arrive at an expanded position. Depending on thecircumstances, e.g., if the flexible, collapsible member 146 is notcontaminated, the flexible, collapsible member 146 may be re-primed byplacing the flexible, collapsible member 146 in the compressed positionagain and starting another cycle. An alarm may be added to audiblysignal when the expanded position has been reached.

Referring now primarily to FIG. 2, a manually-actuated, reduced-pressuresource 240 is shown in an exploded, perspective view. Themanually-actuated, reduced-pressure source 240 includes a flexible,collapsible member 246 disposed between a carrier member 256 and aslider member 268. The carrier member 256 and the slider member 268 areurged away from each other by a constant-force biasing member 278.

The flexible, collapsible member 246 has a first end 248 and a secondend 250. The flexible, collapsible member 246 may hold air or otherfluid in an interior portion. An evacuation port 253 may be located nearthe first end 248 to allow the air or other fluid to exit the interiorspace of the flexible, collapsible member 246. A reduced-pressure port254 may be located near the second end 250. During use, thereduced-pressure port 254 is fluidly coupled to a reduced-pressuredelivery conduit, e.g., reduced-pressure delivery member 122 of FIG. 1,to provide reduced pressure to a system for treating tissue at a woundsite. These ports 253, 254 may be located anywhere on the flexible,collapsible member 246.

In this illustrative embodiment, a nodule 255 is coupled to theflexible, collapsible member 246 near the second end 250. The nodule 255is added for safety reasons. In particular, because the first end 248has one evacuation port 253 and the second end 250 has reduced-pressureport 254 and nodule 255, the flexible, collapsible member 246 can onlybe mated with the carrier member 256 and the slider member 268 in onedirection. Thus, the flexible, collapsible member 246 may only beinstalled in the correct way.

In one illustrative example, the flexible, collapsible member 246 may beformed as bellows. In such an illustrative embodiment, the flexible,collapsible member 246 is formed with corrugated side walls 245 withcorrugations that may move toward and away from one another, resultingin a compression and expansion of compressible bellows. The flexible,collapsible member 246 may be made from any material, e.g., a flexiblepolymer, which allows for the compression and expansion of the bellows.The shape may be rectangular, circular, or any other shape. Theflexible, collapsible member 246 may be coupled to the carrier member256 and slider member 268 by being welded, screwed, glued, bolted,air-lock sealed, snapped or by any other means. The term “coupled”generally includes coupling via a separate object and includes directcoupling. The term “coupled” also encompasses two or more componentsthat are continuous with one another by virtue of each of the componentsbeing formed from the same piece of material. Also, the term “coupled”may include chemical, such as via a chemical bond, mechanical, thermal,or electrical coupling.

The inner chamber of the flexible, collapsible member operates as aclosed system such that the pressure and volume have a definedrelationship, i.e., P₁*V₁=P₂*V₂. The area of an end wall 251 of theflexible, collapsible member 246 experiences pressure and transmits aforce to the slider member 268. The force is proportional to the area(F≈PA). The reduced pressure generated can be controlled by selectingthe force of the constant-force biasing member 278 and controlling thearea of the end wall 251. The pressure developed by themanually-actuated, reduced-pressure source 240 is generally inverselyproportional to the area on the interior portion of the end wall 251 ofthe flexible, collapsible member 246 that faces a slider lateral slidermember 276 (P≈F/A).

The carrier member 256 is shown in this illustrative embodiment ashaving a first socket member 258 and a second socket member 260. As willbe explained further below, the socket members 258 and 260 are sized toreceive a first constant-force coil spring 280 and a secondconstant-force coil spring 282, respectively, and a first arm 270 and asecond arm 272 of the slider member 268, respectively.

The first socket member 258 and second socket member 260 are coupled bya lateral carrier member 262. The lateral carrier member 262 is formedwith a port channel 264. The port channel 264 is sized and configured tosecurely receive, such as by an interference fit, the evacuation port253. The socket members 258 and 260 may be formed with an indicatorwindow 266 through which a scale, markings, or other visual indicia 274on an exterior surface 273 of the slider member 268 may be viewed. Thecarrier member 256 may be formed as a plurality of components that arecoupled through welding, adhesives, bolting, snap fitting, screws, or byany other coupling or may be formed as an integral unit such as bycasting. The two coil springs 280, 282 could be placed in a singlesocket member; in that case, it may be desirable to place the indicatorwindow on the opposite side from the side with springs.

The slider member 268 is formed with a first arm 270 and a second arm272 and has a lateral slider member 276 coupled between the arms 270,272. The lateral slider member 276 has a first port channel 275 and asecond port channel 277 that are sized and configured to securelyreceive, e.g. with an interference fit, the reduced-pressure port 254and the nodule 255 (or simulated port), respectively. The visual indicia274, such as a scale, may be placed on the exterior surface 273 of oneof the arms, e.g., second arm 272.

In this illustrative embodiment, the constant-force biasing member 278includes the first constant-force coil spring 280 and the secondconstant-force coil spring 282. The first constant-force coil spring 280has a fixation portion 284 and a coil portion 286. The fixation portion284 is coupled proximate to a socket opening 259 of the first socketmember 258 and the socket opening 259 is sized to receive the coilportion 286 of the first constant-force coil spring 280. The first arm270 of the slider member 268 is formed with an interface area 271, ormember, that may be concave as shown, and is made to contact the coilportion 286 and to unroll the coil portion 286 or deflect the coilportion 286 as the slider member 268 is manually actuated towards thecarrier member 256.

Referring now primarily to FIGS. 3A and 3B, a schematic cross-section ofthe first socket member 258, first constant-force coil spring 280, andfirst arm 270 are shown initially in an extended position in FIG. 3A,and then in a compressed position in FIG. 3B. Beginning in the extendedposition of FIG. 3A, the coil portion 286 is near its natural freeposition, or length. The fixation portion 284 of the firstconstant-force coil spring 280 is coupled using a coupling device 283,such as a spring retainer or a pin, etc. As the first arm 270 is urgedinto the first socket member 258, the interface area 271 presses againstthe coil portion 286 of the first constant-force coil spring 280 andcauses the coil portion 286 to unroll at least partially and all thewhile the first constant-force coil spring 280 provides a constant forcethat resists the load being placed on the first constant-force coilspring 280.

As the first arm 270 is urged to the first arm's stopping spot as shownin FIG. 3B, and released, the first constant-force coil spring 280 willcontinue to urge the first arm 270 away from and out of the first socketmember 258. Returning again to FIG. 2, it should be understood that thesecond constant-force coil spring 282 interacts with the second socketmember 260 and the second arm 272 in a manner analogous to that shown inFIGS. 3A and 3B for the first constant-force coil spring 280.

In operation, the manually-actuated, reduced-pressure source 240generates a reduced pressure as the manually-actuated, reduced-pressuresource 240 moves from a compressed position as shown in FIG. 4A to anintermediate position shown in FIG. 4B and ending in an extendedposition shown in FIG. 4C. To prepare the manually-actuated,reduced-pressure source 240 for use in a reduced-pressure treatmentsystem, the flexible, collapsible member 246 is placed with theevacuation port 253 in the port channel 264 of the carrier member 256and the reduced-pressure port 254 and the nodule 255 are placed in thefirst port channel 275 and the second port channel 277, respectively. Areduced-pressure delivery conduit may be connected to thereduced-pressure port 254. Then the slider member 268 is urged towardsthe carrier member 256 by manually pressing, or activating, the memberstogether such as, for example, with one's hand. As this is done, theconstant-force coil springs 280 and 282 unwind and themanually-actuated, reduced-pressure source 240 arrives at the compressedposition (see FIGS. 3B and 4A).

Then the manual force that was applied is removed and the springs 280and 282 urge the slider member 268 away from the carrier member 256.This urging starts to expand the flexible, collapsible member 246 andthat places a suction on the reduced-pressure port 254. As gas or otherfluid is received into the reduced-pressure port 254, themanually-actuated, reduced-pressure source 240 again reaches equilibriumas the slider member 268 is moved out from the carrier member at leastto some degree. This process continues through the intermediatepositions all the way until the manually-actuated, reduced-pressuresource 240 reaches a final, or extended, position (see FIGS. 3A and 4C)where either the flexible, collapsible member 246 being completely full,or the springs 280, 282 having reached their beginning position.

Referring now primarily to FIG. 5, another illustrative embodiment of amanually-actuated, constant reduced-pressure source 340 is presented.The manually-actuated, constant reduced-pressure source 340 includes aflexible, collapsible member 346, a carrier member 356, and a slidermember 368. Retention members 383 couple a constant-force biasing member(not shown) within a portion of the carrier member 356. Theconstant-force biasing member provides a force that urges the slidermember 368 away from the carrier member 356 as the manually-actuated,constant reduced-pressure source 340 moves from a compressed position toan extended position.

The carrier member 356 includes a first socket member 358, a secondsocket member 360, and a carrier lateral member 362. The carrier member356 may be formed by component parts that are coupled or may be formedas an integral unit by such means as casting. An indicator 365 may beincluded as a part of the manually-actuated, constant reduced-pressuresource 340 to indicate remaining capacity or movement. As one example,the indicator 365 may be an indicator window 366 formed on the firstsocket member 358 or the second socket member 360 that allows for visualindicia that is attached to a portion of the slider member 368 to beseen and thereby provides an indication of how much further themanually-actuated, constant reduced-pressure source 340 can move beforereaching its fully-extended position. A port channel 364 may be formedon the carrier lateral member 362 to help hold a port, such as areduced-pressure port through which the reduced pressure that isgenerated within the flexible, collapsible member 346 may be deliveredto a reduced-pressure delivery conduit 322, which transmits the reducedpressure on to a system for treating tissue at a wound site.

The slider member 368 has a first arm 370 and a second arm 372. The arms370, 372 are connected by a slider lateral member 376. The sliderlateral member 376 may be snapped into position on the two arms 370,372. In a manner analogous to that shown in FIGS. 3A and 3B, the arms370, 372 may push a constant-force biasing member located within thesocket members 358 and 360.

The flexible, collapsible member 346 has a first end 348 and a secondend 350. A portion of the second end 350 may be formed intentionally tohold fluids, such as exudate that may gather within the interior spaceof the flexible, collapsible member 346. An absorption gel or otherabsorption material may be placed within an interior portion of thecollapsible member, such as near the second end 350. The first end 348of the flexible, collapsible member 346, in this particular illustrativeembodiment, includes a reduced-pressure port that fits within the portchannel 364 on the carrier member 356. The fit, e.g., an interferencefit, may be tight enough to help hold the first end 348 securely to thecarrier member 356 or other means of coupling the first end 348 may beutilized such as fasteners, welding, adhesives, etc. The second end 350of flexible, collapsible member 346 is formed with a channel or grooveor carrier lug 352 that is sized and configured to receive the sliderlateral member 376 and to hold the slider lateral member 376 and therebysecure the second end 350 to the slider member 368.

Referring now primarily to FIG. 6, another illustrative embodiment of amanually-actuated, reduced-pressure apparatus 440 is presented in anexploded perspective view. The manually-actuated, reduced-pressureapparatus 440 includes a flexible, collapsible member 446, a carriermember 456, which includes a housing portion 457, or casing, and a basemember 461. The manually-actuated, reduced-pressure apparatus 440further includes a slider member 468 and a constant-force biasing member478.

The flexible, collapsible member 446 has a first end 448 and a secondend 450. In this embodiment, the first end 448 is coupled inside of aslider member 468 and the second end 450 is coupled to a base pod 463 ofthe base member 461.

The housing portion 457, or casing, of the carrier member 456 is made tosnap into position with the base member 461 to form an integral unit,and this can be done with both a lip portion 490 and with detents, ordetent arms 467, that engage the housing portion 457. The detent arms467 may be used to engage and hold a portion of housing portion 457 anda lip portion 490 may be included to receive and hold the housingportion 457 proximate opening 492. The housing portion 457 may include aslider opening 465 in which the slider member 468 may be slidablycoupled and may be manually depressed within the slider opening 465.

The base member 461 may include a reduced-pressure port (not shown)analogous to reduced-pressure port 254 of FIG. 2 for allowing a deliveryconduit to be attached and to receive and transmit reduced pressure. Thereduced-pressure port 254 is fluidly coupled to an interior space of theflexible, collapsible member 446. The reduced-pressure port 254 mayinclude a counter-bore into the flexible, collapsible member 446 andpreferably into a portion of flexible, collapsible member 446 forholding any fluids that might enter. The port may further include afilter carrier with a filter member; the filter member may include acharcoal pellet filter and a sintered hydrophobic filter.

The slider member 468 is formed with an opening 469. The slider member468 is sized to be operable to slide within a portion of the housingportion 457.

The constant-force biasing member 478 may be a constant-force, coilspring 480 with a fixation portion 484 and a coil portion 486. Thecenter opening of the coil portion 486 may be placed upon a drum or pin488 located on the housing portion 457. The fixation portion 484 may besecured near the slider opening 469.

In the final assembly of the manually-actuated, reduced-pressureapparatus 440, the flexible, collapsible member 446 is coupled to thebase pod 463 where the flexible collapsible member will be held secureand where the flexible, collapsible member 446 is placed into fluidcontact with a reduced-pressure port. The first end 448 of the flexible,collapsible member 446 is placed within opening 469 of the slider member468 and coupled to a portion of the slider member 468. The housingportion 457 is placed over the slider member 468 and the flexible,collapsible member 446 is depressed until the detent arms 467 engage acorresponding receptacle within the opening 492 of the housing portion457 and the lip 490 engages the opening 492. The constant-force biasingmember 478, for example, the constant-force, coil spring 480, is coupledto apparatus 440 by placing the center opening of the coil portion 486onto the drum 488 of the carrier member 456 and coupling the fixationportion 484 near the opening 469 of the slider member 468.

In operation, a reduced-pressure delivery conduit is attached to areduced-pressure port on the base member 461 and then slider member 468may be depressed, or manually-actuated, by pushing the slider member 468down further into slider opening 465 to cause manually-actuated,reduced-pressure apparatus 440 to assume a compressed position in whichthe flexible, collapsible member 446 is collapsed. As the flexible,collapsible member 446 collapses, the air or other fluid within themanually-actuated, reduced-pressure apparatus 440 is forced out of anevacuation port, which also may be on the bottom side of the base member461 (analogous to evacuation port 253 of FIG. 2).

As the coil spring 480 urges the slider member 468 away from the basemember 461 of the carrier member 456, a reduced pressure is developedwithin the interior space of the flexible, collapsible member 446. Thisreduced pressure is communicated to the reduced-pressure port. Theconstant reduced pressure is thus supplied until the flexible,collapsible member 446 is full of air or other fluid and fluids or untilthe resting place or free length of the constant-force, coil spring 480is reached. The apparatus provides a constant reduced pressure with onlysmall variation. Over a period of time the manually-actuated,reduced-pressure apparatus 440 is able to compensate for the ingress bygas or liquid within the flexible, collapsible member 446. The magnitudeof the reduced pressure may be designed and controlled by varying anarea of the end of the flexible, collapsible member 446 as well as thespring force of the constant-force, coil spring 480.

Although the present invention and its advantages have been disclosed inthe context of certain illustrative, non-limiting embodiments, it shouldbe understood that various changes, substitutions, permutations, andalterations can be made without departing from the scope of theinvention as defined by the appended claims. It will be appreciated thatany feature that is described in a connection to any one embodiment mayalso be applicable to any other embodiment.

We claim:
 1. A manually-actuated, reduced-pressure apparatus for use with a reduced-pressure system for treating tissue at a tissue site, the apparatus comprising: a housing; a slider member configured to slide relative to the housing between a first position and a second position; a chamber configured to have a first volume when the slider member is at the first position and a second volume when the slider member is at the second position, the second volume larger than the first volume; and a constant-force biasing member coupled to the housing and the slider member, the constant-force biasing member configured to provide a constant force through a range of motion of the constant-force biasing member, and wherein the constant-force biasing member is configured to urge the slider member from the first position to the second position.
 2. The manually-actuated, reduced-pressure apparatus of claim 1, wherein the constant-force biasing member is configured to transition from an unrolled state to a rolled state and urge the slider member from the first position to the second position.
 3. The manually-actuated, reduced-pressure apparatus of claim 1, wherein the constant-force biasing member comprises a constant-force coil spring.
 4. The manually-actuated, reduced-pressure apparatus of claim 1, wherein the constant-force biasing member comprises a first constant-force coil spring and a second constant-force coil spring coupled to the housing and configured to urge the slider member from the first position to the second position.
 5. The manually-actuated, reduced-pressure apparatus of claim 1, further comprising an indicator configured to indicate movement of the slider member between the first position and the second position.
 6. The manually-actuated, reduced-pressure apparatus of claim 1, wherein the manually-actuated, reduced-pressure apparatus is configured to provide a constant reduced pressure.
 7. The manually-actuated, reduced-pressure apparatus of claim 1, further comprising an evacuation port and a reduced-pressure port coupled to the chamber.
 8. A manually-actuated, reduced-pressure apparatus for treating a tissue site, the apparatus comprising: a housing; a chamber; a wall configured to move relative to the housing; and a constant-force biasing member coupled to the housing and the wall, the constant-force biasing member configured to provide a constant force through a range of motion of the constant-force biasing member; wherein the constant-force biasing member is configured to urge the wall between a first position and a second position; and wherein the chamber is configured to have a first volume when the wall is at the first position and a second volume when the wall is at the second position.
 9. The manually-actuated, reduced-pressure apparatus of claim 8, wherein the constant-force biasing member is configured to transition from an unrolled state to a rolled state and urge the wall from the first position to the second position.
 10. The manually-actuated, reduced-pressure apparatus of claim 8, wherein the constant-force biasing member comprises a constant-force coil spring.
 11. The manually-actuated, reduced-pressure apparatus of claim 8, further comprising an indicator configured to indicate movement of the apparatus between the first position and the second position.
 12. The manually-actuated, reduced-pressure apparatus of claim 8, wherein the manually-actuated, reduced-pressure apparatus is configured to provide a constant reduced pressure.
 13. The manually-actuated, reduced-pressure apparatus of claim 8, further comprising an evacuation port and a reduced-pressure port coupled to the chamber.
 14. A manually-actuated, reduced-pressure apparatus for treating a tissue site with reduced pressure, the apparatus comprising: a carrier member; a slider member configured to move relative to the carrier member; a chamber coupled to the carrier member and the slider member; and a constant-force biasing member coupled to the carrier member and the slider member, the constant-force biasing member configured to provide a constant force through a range of motion of the constant-force biasing member; wherein the chamber is configured to have a different volume through the range of motion of the constant-force biasing member.
 15. The manually-actuated, reduced-pressure apparatus of claim 14, wherein the constant-force biasing member is configured to transition from an unrolled state to a rolled state and move the slider member relative to the carrier member.
 16. The manually-actuated, reduced-pressure apparatus of claim 14, wherein the constant-force biasing member comprises a constant-force coil spring.
 17. The manually-actuated, reduced-pressure apparatus of claim 14, wherein the constant-force biasing member comprises a first constant-force coil spring and a second constant-force coil spring coupled to the carrier member and configured to urge the slider member from a first position to a second position.
 18. The manually-actuated, reduced-pressure apparatus of claim 14, further comprising an indicator window for viewing a portion of the slider member.
 19. The manually-actuated, reduced-pressure apparatus of claim 14, wherein the manually-actuated, reduced-pressure apparatus is configured to provide a constant reduced pressure.
 20. The manually-actuated, reduced-pressure apparatus of claim 14, further comprising an evacuation port and a reduced-pressure port coupled to the chamber. 